A dog trainer told us to get a prong collar - it has prongs that, when the leash is jerked by the handler, are uncomfortable. The prongs aren't sharp and can't pierce the skin, they're just not pleasant if you tug on the leash. At the same time as we yank on the collar, we loudly say 'no!'. At first we had to leave the collar on in the house because it was a reminder of who is the boss but now a simple 'no!' does the trick.... well, mostly :oops: